1. Field of the Invention
The present invention relates to atomic layer deposition (ALD) thin film deposition equipment, and more particularly, to ALD thin film deposition equipment employing a cleaning apparatus and a cleaning method.
2. Description of the Related Art
Thin film deposition equipment forms a predetermined thin film on a wafer by supplying reaction gases to the wafer received within a reactor. This thin film deposition equipment includes chemical vapor deposition (CVD) thin film deposition equipment, atomic layer epitaxy (ALE) thin film deposition equipment, and others, and has been applied to various fields for manufacturing semiconductor devices.
In thin film deposition equipment, a thin film is deposited not only on a wafer by an introduced reaction gas, but a thin film or process byproduct can also be deposited on the inner wall or component of a reactor, or on holes through which reaction gases are sprayed. When particles separated from the thin film or process byproduct drop on a wafer, the characteristics of a thin film deposited on the wafer are deteriorated. This requires a cleaning apparatus and method of effectively removing a thin film or a process byproduct deposited on the inner wall, components or holes of a reactor.
To achieve the above objective, the present invention provides an atomic layer deposition (ALD) thin film deposition equipment having a cleaning apparatus, this equipment including: a reactor in which a wafer is mounted and a thin film is deposited on the wafer; a first reaction gas supply portion for supplying a first reaction gas to the reactor; a second reaction gas supply portion for supplying a second reaction gas to the reactor; a first reaction gas supply line for connecting the first reaction gas supply portion to the reactor; a second reaction gas supply line for connecting the second reaction gas supply portion to the reactor; a first inert gas supply line for supplying an inert gas from an inert gas supply source to the first reaction gas supply line; a second inert gas supply line for supplying the inert gas from the inert gas supply source to the second reaction gas supply line; an exhaust line for exhausting the gas from the reactor to the outside; and a cleaning gas supply line connected to the first reaction gas supply line for supplying a cleaning gas for cleaning the reactor. Here, the cleaning gas is ClF3.
Preferably, the cleaning gas supply line includes: a cleaning gas mass flow controller (MFC) for controlling the flow of a supplied cleaning gas; and at least one valve for allowing or blocking the flow of the cleaning gas. Also, preferably, the cleaning gas supply line further included a filter for filtering out foreign materials existing within the cleaning gas.
To achieve the above ojective, the present invention provides a cleaning method for ALD thin film deposition equipment having a reactor including a reactor block on which a wafer is mounted, a wafer block installed within the reactor block, on which the wafer is seated, and a diffusion plate having a plurality of spray holes formed over the wafer block and a plurality of nozzles slanted toward the inner sidewall of the reactor block to spray a gas toward the edges of the wafer block. This cleaning method includes a main cleaning process performed in a state where no wafers are received within the reactor, for spraying a mixture of a cleaning gas and an inert gas onto the wafer through the spray holes and spraying an inert gas toward the edges of the wafer block through the nozzles.
Preferably, this cleaning method further includes a sub cleaning process performed in a state where no wafers are received within the reactor, for pulse-introducing the cleaning gas into the reactor to induce instantaneous diffusion due to a pressure fluctuation. Also, preferably, this cleaning method further includes a pre-coating process performed in a state where no wafers are received within the reactor, for adhering fine particles remaining within the reactor to the inside surface of the reactor.